Compact padding attachments

ABSTRACT

A compact earth filtering machine adapted to engage with a base vehicle includes a frame including a guide structure for guiding earth being screened. A set of rollers is supported by the frame, with each roller associated with a corresponding sprocket. A mesh, forming a continuous loop and supported by the rollers, is provided for elevating and screening earth provided by the guide structure. A drive chain, coupled along an edge of the mesh, is adapted to engage the sprockets associated with the rollers. A driver is provided for rotating a selected one of the rollers and the associated sprocket to thereby cause the mesh to elevate and screen the earth provided by the guide structure. A transverse conveyor supported by the frame transports earth screened by the mesh to a discharge point adjacent to the compact filtering machine.

FIELD OF INVENTION

The present invention relates in general to padding techniques, and in particular to compact padding attachments.

BACKGROUND OF INVENTION

Underground cables and pipelines are typically emplaced by laying the cable or pipeline in a prepared trench and subsequently backfilling the trench. Some cables and pipelines are susceptible to damage from stones, rocks, or other hard objects in the backfill material. For example, optical fiber communications cables are considered particularly susceptible to damage in this manner, as are polymeric or plastic pipelines. Also steel pipes are increasingly provided with protective polymeric coatings, which must be protected from penetration or damage by hard objects.

Consequently, in the laying of cables and pipelines it is increasingly necessary to backfill the trench with fill material that is free of stones or other hard objects. One way to achieve this is to backfill the trench with sand or other suitable fill (padding) material brought from a remote source of sand or rock-free soil. This approach is expensive and time-consuming. Further, where steel pipe is protectively padded with a layer of sand, the filled trench collects standing water in the porous sand fill, leading to premature corrosion of the pipe. Also, the use of a fill material that is different from the surrounding soil results in a loss of cathodic protection, which leads to premature corrosion of steel pipe.

The alternative is to screen the excavated material dug from the trench to remove stones and other foreign objects and return the screened material to the trench. Several machines, known as padding machines, have been disclosed in the prior art for this purpose. However, existing padding machines are still relatively large and hence must be operated in conjuction with relatively large earthmoving equipment, such as skiploaders and similar pieces of equipment, which are generally unsuitable for small jobs or restricted worksites.

SUMMARY OF INVENTION

The principles of the present invention are generally embodied in compact, self-contained padding machine attachments suitable for use with a range of different base vehicles including, but not limited to, automobiles, ATVs, skid steers, compact loaders, compact track loaders, multi-terrain loaders, and similar relatively small earth moving machines. Preferably, the given base vehicle, which is the prime mover for a padding attachment, mates with that padding attachment in accordance with the universal quick connect standard SAE J2513, although principles of the present invention are applicable to any one of a number of other base vehicle to padding attachment mating techniques.

Padding machine attachments embodying the present inventive principles are exceptionally compact and mobile and hence are particularly suitable for soil screening and padding operations in small or restricted jobsites, such as those found in urban areas. Exemplary applications include smaller landscaping work and pipeline/cable burial jobs where the right of away is restricted or the general working area is confined. Furthermore, these padding machine attachments are more efficient than conventional padding machines given that, even with their reduced size and weight, they still maintain good throughput. Finally, padding machine attachments embodying the present inventive principles do not require operator specific training.

BRIEF DESCRIPTION OF DRAWINGS

For a more complete understanding of the present invention, and the advantages thereof, reference is now made to the following descriptions taken in conjunction with the accompanying drawings, in which:

FIG. 1A is a diagram illustrating a representative compact padding machine attachment and associated compact base vehicle suitable for describing the principles of the present invention;

FIG. 1B is a more detailed diagram of the compact padding machine attachment shown in FIG. 1A, with particular emphasis on the hydraulic subsystems;

FIG. 2A is a perspective view of the main assembly of the compact padding machine attachment shown in FIGS. 1A and 1B;

FIG. 2B is front view of the main assembly of the compact padding machine attachment shown in FIGS. 1A and 1B;

FIG. 2C is a rear view of the main assembly of the compact padding machine attachment of FIGS. 1A and 1B;

FIG. 2D depicts a first side of the main assembly of the compact padding machine attachment of FIGS. 1A and 1B;

FIG. 2E depicts a second (opposing) side of the main assembly of the compact padding machine attachment of FIGS. 1A and 1B;

FIG. 2F is a side cutaway view taken from the first side of the main assembly of the compact padding machine attachment of FIGS. 1A and 1B;

FIG. 2G is a side cutaway view taken from the second side of the main assembly of the compact padding machine attachment of FIGS. 1A and 1B;

FIG. 2H is a top view of the main assembly of the compact padding machine attachment of FIGS. 1A and 1B;

FIG. 2I is a top cutaway view of the main assembly of the compact padding machine attachment of FIGS. 1A and 1B;

FIG. 2J is a front cutaway view of the main assembly of the compact padding machine attachment of FIGS. 1A and 1B;

FIG. 2K is another top view of the main assembly of the compact padding attachment of FIGS. 1A and 1B with the inclined conveyor in place;

FIG. 2L is another side view of the main assembly of the compact padding attachment of FIGS. 1A and 1B with the inclined conveyor in place; and

FIGS. 3A and 3B are detailed partial views of the wire mesh conveyor of FIG. 1B with particular emphasis on the positive drive chain mechanism.

DETAILED DESCRIPTION OF THE INVENTION

The principles of the present invention and their advantages are best understood by referring to the illustrated embodiment depicted in FIGS. 1-3 of the drawings, in which like numbers designate like parts. Additionally, the following issued patents are incorporated herein by reference for all purposes: U.S. Pat. No. 5,097,610 to Bishop for Compact Padding Machine, issued Mar. 24, 1992; U.S. Pat. No. 5,261,171 to Bishop for Pipeline Padding Machine Attachment For A Vehicle, issued Nov. 16, 1993; U.S. Pat. No. 5,479,726 to Bishop for Compact Padding Machine, issued Jan. 2, 1996; U.S. Pat. No. 5,540,003 to Osadchuk for Padding Machine With Shaker For Separator, issued Jul. 30, 1996; and U.S. Pat. No. 5,741,087 to Osadchuk for Chain Separator For Padding Machine, issued Apr. 21, 1998.

FIG. 1A is a perspective drawing of a compact padder attachment 100 embodying the principles of the present invention. In FIG. 1A, compact padder attachment 100 is shown attached to a small tracked earth moving (base) vehicle 101, such as a Bobcat T300 compact earth mover. It should be noted however that compact padder attachment 100 can be advantageously utilized with a wide range of different base vehicles, including wheeled compact earth movers, cars, light trucks, ATVs, and the like.

Generally, compact padder attachment 100 includes a blade 102 and a pair of front wings 103 a-103 b, which together funnel earth disposed along the side of a trench to a wire mesh inclined elevator 104 that transports earth upwards between sidewalls 105 a-105 b towards discharge guide 107.

An elevator conveyor, not visible in FIGS. 1A and 1B, receives padding material falling through inclined wire mesh elevator 104 and carries that padding material to a discharge point above transverse conveyor 106. The padding material deposited by the elevator conveyor, as well as any padding material falling through the upper part of mesh conveyor 104, is discharged to a lateral deposit point by transverse conveyor 106. The deposit point could be a trench being filled during a cable or pipeline padding operation, or could be a surface area, as might be under work during a landscaping operation.

Larger clusters of earth, rocks, and other unwanted debris are conveyed to discharge guide 107 where they fall through to the ground surface below and away from the trench. As discussed further below, wire mesh elevator 104 also includes a shaker assembly that assists in separating padding material from unwanted debris.

FIG. 1B is a more detailed drawing of compact padder attachment 100, which emphasizes the hydraulic subsystems used to drive the moving portions of compact padder attachment 100. In particular, a manifold 108 receives driving hydraulic fluid from base vehicle 101 through a set of conventional hydraulic hoses. Hydraulic motor 109, which is coupled to hydraulic manifold 108 through conventional hydraulic lines, drives wire mesh inclined conveyer 104. A second hydraulic motor 110, also operating off of hydraulic manifold 108, drives the belt of transverse conveyer 106. Finally, a third hydraulic motor 111 provides for the lateral adjustment of the ends of transverse conveyer 106 using a rack and pinion system described in further detail below.

FIGS. 2A-2L are a series of views illustrating the main assembly 200 of compact padder attachment 100. Specifically, in the views provided in FIGS. 2A-2L, blade 102, wire mesh conveyer 104, as well as the belt of transverse conveyer 106 has been removed such that various underlying structures are visible.

As shown in FIG. 2A, main assembly 200 is based on a steel frame including sides 201 a and 201 b. A pair of back plates 202 a and 202 b are provided for attachment to base vehicle 101. In the preferred embodiment, back plates 202 a and 202 b are adapted to provide an interface to an SAE J2513 universal quick-connect standard connector on base vehicle 101, although other padding machine attachment to base vehicle interfaces may be used in alternate embodiments. A pair of skids 203 a and 203 b on frame sides 201 a and 201 b allow compact padder attachment 100 to slide along the ground in a relatively smooth fashion and with minimal damage. In FIG. 2A, transverse conveyor 106 is shown in its folded position, as typically used during storage and transport of compact padder attachment 100.

FIG. 2B provides a front view of main assembly 200. Generally, wire mesh conveyer 104 and the inclined conveyor rotate around a set of rollers and roller shafts, which also provide a shaker function. As shown in the front view of FIG. 2B, the set of rollers and roller shafts include front lower roller 204, central roller 205, lower roller shaft 206, upper roller shaft 207, and upper roller 208. Hydraulic motor 109 of FIG. 1B drives the rotation of upper roller 208 and hence the motion of wire mesh conveyer 104.

Front lower roller 204 includes a notch 234 and central roller 205 includes a notch 235, each adapted to engage a corresponding protrusion on the belt of the elevator conveyor, described in further detail below. Generally, the belt of the inclined conveyor loops around the surfaces of front lower roller 204 and central roller 205. A rectangular protrusion on the bottom of elevator conveyor belt mates with notches 234 and 235 to minimize lateral belt movement.

FIG. 2C, which provides a rear view of main assembly 200, shows the third roller upon which wire mesh conveyer 104 travels, namely, rear lower roller 210. As visible in this view, rear lower roller 210 rotates around a shaft 211 while upper roller 208 rotates around a shaft 209. A pair of sprockets 240 a and 240 b on shaft 211 of rear lower roller 210 are provided for engaging the positive drive chains of wire mesh conveyor 104, discussed in detail below.

With specific respects to upper roller 208, bracket 212 is provided for supporting hydraulic motor 109 of FIG. 1B while a shelf 213 provides a support for hydraulic manifold 108, also shown in FIG. 1B. Central roller 205 rotates around a shaft 214, as shown in FIG. 2C.

FIGS. 2D AND 2E are respective opposing side views of main assembly 200 of compact padder attachment 100. As shown in FIGS. 2D AND 2E, front lower roller 204 rotates around a shaft 215 journalized in bearings 216 a and 216 b. Additionally, shaft 214 for central roller 205 is supported by a set of adjusters 217 a-217 b. Adjusters 217 a-217 b allow for the adjustment of the pressure exerted by central roller 205 and lower front roller 204 onto the inclined conveyor belt (discussed below). Similarly, a pair of adjusters 220 a and 220 b allow the pressure exerted on wire mesh conveyer 104 by rear lower roller 210 to be adjusted. In FIGS. 2D and 2E, transverse conveyor 106 is shown in its operational (unfolded) configuration.

A shield 218, supported on shield arm 219, deflects padding material falling through wire mesh conveyer 104 towards transverse conveyer 106.

As mentioned above, the lateral extension of transverse conveyer 106 (to either side) is controllable through a rack and pinion system. This rack and pinion system includes pinion rollers 222 a-222 b and pinion gears 223 a-223 d, as shown in FIGS. 2D and 2E. As also particularly shown in FIG. 2E, shaft 209 of upper roller 208 rotates within a set of roller bearings 221.

FIGS. 2F and 2G are respective cross sections of the side views shown in FIGS. 2D and 2E. In particular, as shown in FIGS. 2F and 2G, each end of shaft 215 of front lower roller 206 is provided with a sprocket 224 a-224 b. Each end of lower roller shaft 206 is provided with an offset sprocket 226 a-226 b while each end of upper roller shaft 207 is provided with an offset sprocket 227 a-227 b. Finally, each end of shaft 209 of upper roller 208 is provided with a sprocket 225 a-225 b.

Sprockets 226 a-226 b and 227 a-227 b are “offset” because their center points are not concentric with the center points of corresponding roller shafts 206 and 207. Consequently, the rotation of sprockets 226 a-226 b and 227 a-227 b is eccentric, which imparts vibration energy into the mesh of wire mesh conveyor 104 to effectuate shaking.

FIG. 2H is a top view of main assembly 200 illustrating a selected number of the structures discussed in detail above. FIG. 2I is a top sectional view emphasizing the particular structures of transverse conveyer 106. (In FIGS. 2H and 2I, transverse conveyor 106 is shown in the folded configuration.) Additional features of transverse conveyer 106 are shown in the front sectional view provided as FIG. 2J.

Transverse conveyer 106, as shown in FIG. 2I with the belt removed, is based on a pair of substantially parallel rails 229 a and 229 b and a set of spacers, two of which are shown at 230 a and 230 b. The belt (not shown) of transverse conveyer 106 moves across a set of rollers, two of which are shown at 231 a and 231 b, as driven by hydraulic motor 110. Each rail 229 a and 229 b supports a rack, one of which 232 a is shown in FIG. 2J. Racks 232 interface with pinion gears 223 a-223 d to allow the lateral extension of the ends of transverse conveyer 106 to be adjusted in response to the drive provided by hydraulic motor 111. The interface between rack 232 a and pinion gears 223 a and 223 d is shown in FIG. 2J.

The inclined conveyor belt is shown installed in FIGS. 2K and 2L, which are respectively alternate top and side views of main assembly 200. In particular, as shown in FIG. 2K, elevator belt 236 forms a continuous loop around front lower roller 204 and central roller 205. Protrusion 237, extending from inner surface of elevator belt 236, interfaces with notch 234 on front lower roller 204 and notch 235 on central roller 205. Advantageously, the interfaces between notches 234 and 235 and protrusion 237 minimize transverse movement of elevator belt 236.

FIG. 2L shows elevator conveyor belt 236 forming a continuous loop around central roller 205. Adjusters 217 a-217 b allow the appropriate amount of tension applied to the continuous loop of elevator conveyor belt 236 around front lower roller 204 and central roller 205 to be controlled.

FIGS. 3A and 3B are more detailed partial views of the upper side of wire mesh conveyor 104. As shown in FIG. 3A, wire mesh conveyor 104 includes mesh 301 of interconnected steel links, which allow screened padding material to fall through towards the elevator conveyor belt 236 and transverse conveyor 106, while at the same time forcing larger clusters of earth, rocks, and debris to be carried towards discharge guides 107 of FIG. 1A.

The lateral edges of mesh 301 are connected to corresponding positive drive chains 302 a and 302 b. In particular, positive drive chain 302 a interfaces with sprocket 224 a associated with front lower roller 204, sprocket 225 a associated with upper roller 208, offset sprocket 226 a associated with lower roller shaft 206, offset sprocket 227 a associated with upper roller shaft 207, and sprocket 240 a associated with rear lower roller 210, shown in FIGS. 2C and 2F. Similarly, positive drive chain 302 b interfaces with sprocket 224 b associated with front lower roller 204, sprocket 225 b associated with upper roller 208, offset sprocket 226 b associated with lower roller shaft 206, offset sprocket 227 b associated with upper roller shaft 207, and sprocket 240 b associated with rear lower roller 210, shown in FIGS. 2C and 2G.

FIG. 3B illustrates a typical sprocket—drive chain interface, using sprocket 225 b associated with upper roller 208 and positive drive chain 302 b as an example.

Advantageously, in this configuration, only a single hydraulic motor 109 (FIG. 1A) is required to drive wire mesh conveyor 104, as well as the shaker assembly comprised of offset sprockets 226 a-226 b and lower roller shaft 208, and offset sprockets 227 a-227 b and upper roller shaft 209. (This shaker assembly imparts vibrational energy into mesh 301, which in turn facilitates the soil screening process by breaking up clusters of fine soil and by agitating wet soil.) Advantageously, since sprockets 226 a-226 b and 227 a-227 b are driven directly by positive drive chains 302 a-302 b, the dedicated shaker assembly drive motor normally found in conventional padding systems is no longer required.

As shown in the top view of FIG. 2H, discharge guide 107 defines an aperture 233 that advantageously directs the rejected materials that do not pass through mesh 301 (FIG. 3A) to the ground surface under and between the tracks or tires of base vehicle 101 of FIG. 1A. Furthermore, discharge guide 107 also protects the front of base vehicle 101 and the local hydraulics from being struck by large debris being discharged from compact padding attachment 100.

Although the invention has been described with reference to specific embodiments, these descriptions are not meant to be construed in a limiting sense. Various modifications of the disclosed embodiments, as well as alternative embodiments of the invention, will become apparent to persons skilled in the art upon reference to the description of the invention. It should be appreciated by those skilled in the art that the conception and the specific embodiment disclosed might be readily utilized as a basis for modifying or designing other structures for carrying out the same purposes of the present invention. It should also be realized by those skilled in the art that such equivalent constructions do not depart from the spirit and scope of the invention as set forth in the appended claims.

It is therefore contemplated that the claims will cover any such modifications or embodiments that fall within the true scope of the invention. 

1. A compact earth filtering machine adapted to engage with a base vehicle comprising: a frame including a guide structure for guiding earth being screened; a set of rollers supported by the frame, each roller associated with a corresponding sprocket; a mesh forming a continuous loop and supported by the rollers for elevating and screening earth directed thereto by the guide structure; a drive chain coupled along at least one edge of the mesh and adapted to engage the sprocket associated with each roller; a driver for rotating a selected one of the rollers and the associated sprocket to thereby cause the mesh to elevate the earth directed thereto by the guide structure; and a transverse conveyor supported by the frame for transporting screened earth screened by the mesh to a discharge point adjacent to the compact filtering machine.
 2. The compact earth filtering machine of claim 1, further comprising: a rack and pinion system for laterally moving an end of the transverse conveyor relative to the frame and thereby laterally change a spacing of the discharge point from the frame.
 3. The compact earth filtering machine of claim 1, further comprising an interface for engaging the base vehicle in accordance with the SAE J2513 quick-connect standard.
 4. The compact earth filtering machine of claim 1, further comprising a shaker assembly driven the drive chain.
 5. The compact earth filtering machine of claim 4, wherein the shaker assembly comprises: a roller shaft supported by the frame; and an offset sprocket for engaging the drive chain.
 6. The compact earth filtering machine of claim 1, further comprising an inclined conveyor disposed beneath the mesh for transporting earth filtered by the mesh to a point above the transverse conveyor, the inclined conveyor comprising: a second set of rollers, at least one of the second set of rollers including a notch and at least one of the second set of rollers associated with a sprocket adapted to engage the drive chain; and a belt for transporting the filtered earth and having a protrusion on a selected surface adapted to engage the notch to reduce lateral movement of the belt.
 7. The compact earth filtering machine of claim 1, wherein the transverse conveyor comprises a set of rollers and a belt for transporting filtered earth, at least one of the set of rollers including a notch and the belt having a protrusion for engaging the notch for reducing lateral movement of the belt.
 8. A padding machine comprising: a support structure including guides for guiding earth being screened; a set of rollers supported by the support structure; a continuous mesh loop supported by the rollers for screening received earth guided thereto by the guides; a driver for rotating a selected one of the set of rollers and thereby cause the mesh loop to elevate and screen the received earth; and a transverse conveyor system for transporting earth screened by the mesh to a discharge point adjacent to the padding machine, comprising: a frame including first and second spaced apart rails supporting another set of rollers, a continuous-loop belt, and a driver for rotating the continuous-loop belt over the another set of rollers; a rack disposed on at least one the rails of the frame; and a pinion gear for engaging the rack and a pinion driver supported by the support structure for selectively rotating the pinion gear for laterally moving an end of the transverse conveyor relative to the support structure and thereby laterally change a spacing of the discharge point from the support structure.
 9. The padding machine of claim 8, wherein each roller of the set of rollers is coupled to a sprocket and the padding machine further comprises: a drive chain coupled along at least one edge of the mesh loop and adapted to engage the sprockets coupled to the rollers of the set of rollers and thereby cause the mesh loop to move in response to the driver.
 10. The padding machine of claim 9, further comprising a shaker driven by the drive chain for causing the mesh loop to vibrate while elevating and screening earth.
 11. The padding machine of claim 10, wherein the shaker comprises at least one offset sprocket adapted to engage the drive chain.
 12. The padding machine of claim 8, further comprising an SAE J2513 standard quick-connect interface for coupling the support structure with an associated vehicle.
 13. The padding machine of claim 8, further comprising an inclined conveyor disposed beneath at least a portion of the mesh loop for transporting screened earth falling though the mesh loop to a point above the transverse conveyor, the inclined conveyor comprising: a further set of rollers supported by the support structure, at least one of the further set of rollers having a notch; and a continuous-loop belt moving across the further set of rollers and including a protrusion adapted to engage the notch to thereby reduce lateral movement of the belt.
 14. The padding machine of claim 9, further comprising an inclined conveyor disposed beneath at least a portion of the mesh loop for transporting screened earth falling though the mesh loop to a point above the transverse conveyor, wherein the inclined conveyor includes at least one roller driven by the drive chain.
 15. A padding attachment for use with a base vehicle comprising: a support structure including guides for guiding earth being screened; an interface structure coupled to the support structure for interfacing with the base vehicle; a mesh elevator including: a set of rollers each including a shaft; first and second sprockets coupled to opposing ends of each shaft; a continuous-loop mesh supported by the rollers; first and second drive chains coupled along opposing edges of the mesh and adapted to engage a corresponding one of the sprockets coupled to each shaft; and a driver for rotating a selected one of the rollers and the associated sprockets to thereby cause the mesh to elevate the earth directed thereto by the guides; and a transverse conveyor system including a transverse conveyor for transporting earth filtered by the mesh elevator to a discharge point adjacent to a selected side of the padding attachment, the transverse conveyor system including a rack and pinion system for laterally moving the transverse conveyor to change the spacing between the discharge point and the selected side of the padding attachment.
 16. The padding attachment of claim 15, wherein the support structure further includes a discharge guide structure for discharging debris filtered by the mesh to a point away from the discharge point of the filtered earth.
 17. The padding attachment of claim 15, further comprising an inclined belt conveyor disposed beneath the mesh elevator for transporting earth filtered by the mesh to a point above the transverse conveyor.
 18. The padding attachment of claim 15, wherein the driver comprises a hydraulic motor responsive to a hydraulic system of the base vehicle.
 19. The padding attachment of claim 15, wherein the transverse conveyor system includes a first hydraulic motor for driving the transverse conveyor and a second hydraulic motor for driving the rack and pinion system, the first and second hydraulic motors responsive to a hydraulic system of the base vehicle.
 20. The padding attachment of claim 15, wherein the interface structure is in compliance with the SAE J2513 quick-connect standard. 